Best Lewis Structure
The Lewis structure that is closest to your structure is determined.
The hybridization of the atoms in this idealized Lewis structure
is given in the table below.
Please note that your structure can't be well described by a single
Lewis structure, because of extensive delocalization.
Hybridization in the Best Lewis Structure
1. A antibonding orbital for Si1-Si2 with 1.9862 electrons
__has 49.99% Si 1 character in a sp1.28 hybrid
__has 50.01% Si 2 character in a sp1.28 hybrid
2. A bonding orbital for Si1-Si2 with 1.1651 electrons
__has 50.01% Si 1 character in a sp1.28 hybrid
__has 49.99% Si 2 character in a sp1.28 hybrid
23. A lone pair orbital for Si1 with 1.0700 electrons
__made from a p-pi orbital ( 99.17% p 0.83% d)
24. A lone pair orbital for Si1 with 0.9740 electrons
__made from a sp0.72 hybrid
25. A lone pair orbital for Si1 with 0.6904 electrons
__made from a p-pi orbital ( 98.84% p 1.16% d)
26. A lone pair orbital for Si2 with 1.0700 electrons
__made from a p-pi orbital ( 99.17% p 0.83% d)
27. A lone pair orbital for Si2 with 0.9738 electrons
__made from a sp0.72 hybrid
28. A lone pair orbital for Si2 with 0.6903 electrons
__made from a p-pi orbital ( 98.84% p 1.16% d)
29. A lone pair orbital for Si3 with 0.8059 electrons
__made from a s0.76 p3 hybrid
30. A lone pair orbital for Si3 with 0.5865 electrons
__made from a p-pi orbital ( 98.76% p 1.24% d)
31. A lone pair orbital for Si3 with 0.3099 electrons
__made from a p-pi orbital ( 98.55% p 1.45% d)
32. A lone pair orbital for Si3 with 1.9654 electrons
__made from a sp0.24 hybrid
33. A lone pair orbital for Si4 with 0.8059 electrons
__made from a s0.76 p3 hybrid
34. A lone pair orbital for Si4 with 0.5865 electrons
__made from a p-pi orbital ( 98.76% p 1.24% d)
35. A lone pair orbital for Si4 with 0.3099 electrons
__made from a p-pi orbital ( 98.55% p 1.45% d)
36. A lone pair orbital for Si4 with 1.9654 electrons
__made from a sp0.24 hybrid
-With core pairs on:Si 1 Si 1 Si 1 Si 1 Si 1 Si 2 Si 2 Si 2 Si 2 Si 2 Si 3 Si 3 Si 3 Si 3 Si 3 Si 4 Si 4 Si 4 Si 4 Si 4 -
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Donor Acceptor Interactions in the Best Lewis Structure
The localized orbitals in your best Lewis structure
can interact strongly. A filled bonding or lone pair orbital can
act as a donor and an empty or filled bonding, antibonding, or
lone pair orbital can act as an acceptor. These
interactions can strengthen and weaken bonds. For example, a
lone pair donor->antibonding acceptor orbital interaction
will weaken the bond
associated with the antibonding orbital. Conversly, an interaction
with a bonding pair as the acceptor will strengthen the bond.
Strong electron delocalization in your best Lewis structure will
also show up as donor-acceptor interactions.
Interactions greater than 20 kJ/mol for bonding and lone pair
orbitals are listed below.
The interaction of antibonding donor orbital, 1, for Si1-Si2 with
the second lone pair acceptor orbital, 24, for Si1 is 384. kJ/mol.
The interaction of antibonding donor orbital, 1, for Si1-Si2 with
the second lone pair acceptor orbital, 27, for Si2 is 384. kJ/mol.
The interaction of bonding donor orbital, 2, for Si1-Si2 with
the second lone pair acceptor orbital, 24, for Si1 is 3537 kJ/mol.
The interaction of bonding donor orbital, 2, for Si1-Si2 with
the second lone pair acceptor orbital, 27, for Si2 is 3533 kJ/mol.
The interaction of antibonding donor orbital, 1, for Si1-Si2 with
the second lone pair acceptor orbital, 29, for Si3 is 34.1 kJ/mol.
The interaction of bonding donor orbital, 2, for Si1-Si2 with
the third lone pair acceptor orbital, 30, for Si3 is 243. kJ/mol.
The interaction of lone pair donor orbital, 23, for Si1 with
the third lone pair acceptor orbital, 30, for Si3 is 947. kJ/mol.
The interaction of the second lone pair donor orbital, 24, for Si1 with
the second lone pair acceptor orbital, 29, for Si3 is 1710 kJ/mol.
The interaction of the second lone pair donor orbital, 24, for Si1 with
the third lone pair acceptor orbital, 30, for Si3 is 141. kJ/mol.
The interaction of the third lone pair donor orbital, 25, for Si1 with
the 4th lone pair acceptor orbital, 31, for Si3 is 498. kJ/mol.
The interaction of lone pair donor orbital, 26, for Si2 with
the third lone pair acceptor orbital, 30, for Si3 is 947. kJ/mol.
The interaction of the second lone pair donor orbital, 27, for Si2 with
the second lone pair acceptor orbital, 29, for Si3 is 1710 kJ/mol.
The interaction of the second lone pair donor orbital, 27, for Si2 with
the third lone pair acceptor orbital, 30, for Si3 is 141. kJ/mol.
The interaction of the third lone pair donor orbital, 28, for Si2 with
the 4th lone pair acceptor orbital, 31, for Si3 is 498. kJ/mol.
The interaction of antibonding donor orbital, 1, for Si1-Si2 with
the second lone pair acceptor orbital, 33, for Si4 is 34.1 kJ/mol.
The interaction of bonding donor orbital, 2, for Si1-Si2 with
the third lone pair acceptor orbital, 34, for Si4 is 243. kJ/mol.
The interaction of lone pair donor orbital, 23, for Si1 with
the third lone pair acceptor orbital, 34, for Si4 is 947. kJ/mol.
The interaction of the second lone pair donor orbital, 24, for Si1 with
the second lone pair acceptor orbital, 33, for Si4 is 1710 kJ/mol.
The interaction of the second lone pair donor orbital, 24, for Si1 with
the third lone pair acceptor orbital, 34, for Si4 is 142. kJ/mol.
The interaction of the third lone pair donor orbital, 25, for Si1 with
the 4th lone pair acceptor orbital, 35, for Si4 is 498. kJ/mol.
The interaction of lone pair donor orbital, 26, for Si2 with
the third lone pair acceptor orbital, 34, for Si4 is 947. kJ/mol.
The interaction of the second lone pair donor orbital, 27, for Si2 with
the second lone pair acceptor orbital, 33, for Si4 is 1710 kJ/mol.
The interaction of the second lone pair donor orbital, 27, for Si2 with
the third lone pair acceptor orbital, 34, for Si4 is 141. kJ/mol.
The interaction of the third lone pair donor orbital, 28, for Si2 with
the 4th lone pair acceptor orbital, 35, for Si4 is 498. kJ/mol.
The interaction of lone pair donor orbital, 32, for Si3 with
the lone pair acceptor orbital, 23, for Si1 is 80.1 kJ/mol.
The interaction of lone pair donor orbital, 32, for Si3 with
the second lone pair acceptor orbital, 24, for Si1 is 27.9 kJ/mol.
The interaction of lone pair donor orbital, 32, for Si3 with
the lone pair acceptor orbital, 26, for Si2 is 80.0 kJ/mol.
The interaction of lone pair donor orbital, 32, for Si3 with
the second lone pair acceptor orbital, 27, for Si2 is 27.9 kJ/mol.
The interaction of lone pair donor orbital, 32, for Si3 with
the second lone pair acceptor orbital, 29, for Si3 is 125. kJ/mol.
The interaction of lone pair donor orbital, 32, for Si3 with
the second lone pair acceptor orbital, 33, for Si4 is 6.31 kJ/mol.
The interaction of lone pair donor orbital, 36, for Si4 with
the lone pair acceptor orbital, 23, for Si1 is 80.0 kJ/mol.
The interaction of lone pair donor orbital, 36, for Si4 with
the second lone pair acceptor orbital, 24, for Si1 is 27.9 kJ/mol.
The interaction of lone pair donor orbital, 36, for Si4 with
the lone pair acceptor orbital, 26, for Si2 is 80.1 kJ/mol.
The interaction of lone pair donor orbital, 36, for Si4 with
the second lone pair acceptor orbital, 27, for Si2 is 27.9 kJ/mol.
The interaction of lone pair donor orbital, 36, for Si4 with
the second lone pair acceptor orbital, 29, for Si3 is 6.31 kJ/mol.
The interaction of lone pair donor orbital, 36, for Si4 with
the second lone pair acceptor orbital, 33, for Si4 is 125. kJ/mol.
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Molecular Orbital Energies
The orbital energies are given in eV, where 1 eV=96.49 kJ/mol.
Orbitals with very low energy are core 1s orbitals.
More antibonding orbitals than you might expect are sometimes
listed, because d orbitals are always included for heavy
atoms and p orbitals are included for H atoms.
Up spins are shown with a ^ and down spins are shown as v.
32 ----- -2.089
31 ----- -3.013
30 ----- -3.245
29 ----- -4.502
28 -^-v- -5.609
27 -^-v- -5.830
26 -^-v- -6.476
25 -^-v- -6.804
24 -^-v- -8.483
23 -^-v- -10.20
22 -^-v- -12.16
21 -^-v- -15.15
20 -^-v- -94.41 19 -^-v- -94.41
18 -^-v- -94.52 17 -^-v- -94.53
16 -^-v- -94.71 15 -^-v- -94.71
14 -^-v- -94.94 13 -^-v- -94.94
12 -^-v- -95.08 11 -^-v- -95.08
10 -^-v- -95.28 9 -^-v- -95.28
8 -^-v- -136.9 7 -^-v- -136.9
6 -^-v- -137.4 5 -^-v- -137.4
4 -^-v- -1772. 3 -^-v- -1772.
2 -^-v- -1773. 1 -^-v- -1773.
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Total Electronic Energy
The total electronic energy is a very large number, so by convention
the units are given in atomic units, that is Hartrees (H). One
Hartree is 2625.5 kJ/mol. The energy reference is for totally
dissociated atoms. In other words, the reference state is a gas
consisting of nuclei and electrons all at infinite distance from
each other. The electronic energy includes all electric
interactions and the kinetic energy of the electrons. This energy
does not include translation, rotation, or vibration of the
the molecule.
Total electronic energy = -1158.0023023543 Hartrees
* Also check the tetrahedral structure
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